TPC/AliTPCv2.cxx

   1 /**************************************************************************
   2  * Copyright(c) 1998-1999, ALICE Experiment at CERN, All rights reserved. *
   3  *                                                                        *
   4  * Author: The ALICE Off-line Project.                                    *
   5  * Contributors are mentioned in the code where appropriate.              *
   6  *                                                                        *
   7  * Permission to use, copy, modify and distribute this software and its   *
   8  * documentation strictly for non-commercial purposes is hereby granted   *
   9  * without fee, provided that the above copyright notice appears in all   *
  10  * copies and that both the copyright notice and this permission notice   *
  11  * appear in the supporting documentation. The authors make no claims     *
  12  * about the suitability of this software for any purpose. It is          *
  13  * provided "as is" without express or implied warranty.                  *
  14  **************************************************************************/
  15
  16 /*
  17 $Log$
  18 Revision 1.43  2002/10/14 14:57:43  hristov
  19 Merging the VirtualMC branch to the main development branch (HEAD)
  20
  21 Revision 1.40.6.2  2002/07/24 10:09:01  alibrary
  22 Updating VirtualMC
  23
  24 Revision 1.42  2002/06/12 14:56:56  kowal2
  25 Added track length to the reference hits
  26
  27 Revision 1.41  2002/05/27 14:33:15  hristov
  28 The new class AliTrackReference used (M.Ivanov)
  29
  30 Revision 1.40  2002/01/21 17:12:00  kowal2
  31 New track hits structure using root containers
  32
  33 Revision 1.39  2001/05/16 14:57:25  alibrary
  34 New files for folders and Stack
  35
  36 Revision 1.38  2001/05/08 16:03:06  kowal2
  37 Geometry update according to the latest technical spec.
  38
  39 Revision 1.37  2001/04/27 15:23:07  kowal2
  40 Correct materian in the central part of the inner containment vessel
  41
  42 Revision 1.36  2001/04/26 06:15:12  kowal2
  43 Corrected bug in the inner containment vessel (cones)
  44
  45 Revision 1.35  2001/04/24 11:17:33  kowal2
  46 New TPC geometry.
  47
  48 Revision 1.34  2001/04/23 10:20:18  hristov
  49 Constant casted to avoid ambiguity
  50
  51 Revision 1.33  2001/04/20 08:16:47  kowal2
  52 Protection against too small betaGamma. Thanks to Ivana and Yves.
  53
  54 Revision 1.32  2001/03/13 13:07:34  kowal2
  55 Corrected bug in the TPC mother volume geometry.
  56 Thanks to A. Morsch
  57
  58 Revision 1.31  2000/11/30 11:48:50  kowal2
  59 TLorentzVector.h adde to satisfy the latest changes by Federico
  60
  61 Revision 1.30  2000/11/14 10:48:57  kowal2
  62 Correct material used for TSA4. Thanks to J. Barbosa.
  63
  64 Revision 1.29  2000/11/06 17:24:10  kowal2
  65 Corrected bug in the outer containment vessel and
  66 the outer field cage geometry.
  67 Thanks to J. Barbosa.
  68
  69 Revision 1.28  2000/11/02 16:55:24  kowal2
  70 Corrected bug in the inner containment vessel geometry.
  71 Thanks to J. Belikov
  72
  73 Revision 1.27  2000/11/02 07:24:11  kowal2
  74 Correction in the TPC geometry.
  75 Changes due to the new hit structure.
  76
  77 Revision 1.26  2000/10/05 16:16:29  kowal2
  78 Corrections of the hit recording algorithm.
  79
  80 Revision 1.25  2000/10/02 21:28:18  fca
  81 Removal of useless dependecies via forward declarations
  82
  83 Revision 1.24  2000/08/28 10:02:30  kowal2
  84 Corrected bug in the StepManager
  85
  86 Revision 1.23  2000/07/10 20:57:39  hristov
  87 Update of TPC code and macros by M.Kowalski
  88
  89 Revision 1.22  2000/06/30 12:07:50  kowal2
  90 Updated from the TPC-PreRelease branch
  91
  92 Revision 1.21.2.4  2000/06/26 07:39:42  kowal2
  93 Changes to obey the coding rules
  94
  95 Revision 1.21.2.3  2000/06/25 08:38:41  kowal2
  96 Splitted from AliTPCtracking
  97
  98 Revision 1.21.2.2  2000/06/16 12:58:13  kowal2
  99 Changed parameter settings
 100
 101 Revision 1.21.2.1  2000/06/09 07:15:07  kowal2
 102
 103 Defaults loaded automatically (hard-wired)
 104 Optional parameters can be set via macro called in the constructor
 105
 106 Revision 1.21  2000/05/15 10:00:30  kowal2
 107 Corrected bug in the TPC geometry, thanks to Ivana Hrivnacova
 108
 109 Revision 1.20  2000/04/17 09:37:33  kowal2
 110 removed obsolete AliTPCDigitsDisplay.C
 111
 112 Revision 1.19.8.2  2000/04/10 08:31:52  kowal2
 113
 114 Different geometry for different sectors
 115 Updated readout chambers
 116 Some modifications to StepManager by J.Belikov
 117
 118 Revision 1.19.8.1  2000/04/10 07:56:53  kowal2
 119 Not used anymore - removed
 120
 121 Revision 1.19  1999/11/04 17:28:07  fca
 122 Correct barrel part of HV Degrader
 123
 124 Revision 1.18  1999/10/14 16:52:08  fca
 125 Only use PDG codes and not GEANT ones
 126
 127 Revision 1.17  1999/10/08 06:27:23  fca
 128 Corrected bug in the HV degrader geometry, thanks to G.Tabary
 129
 130 Revision 1.16  1999/10/04 13:39:54  fca
 131 Correct array index problem
 132
 133 Revision 1.15  1999/09/29 09:24:34  fca
 134 Introduction of the Copyright and cvs Log
 135
 136 */
 137
 138 //
 139 ///////////////////////////////////////////////////////////////////////////////
 140 //                                                                           //
 141 //  Time Projection Chamber version 2 -- detailed TPC and slow simulation    //
 142 //                                                                           //
 143 //Begin_Html
 144 /*
 145 <img src="picts/AliTPCv2Class.gif">
 146 */
 147 //End_Html
 148 //                                                                           //
 149 //                                                                           //
 150 ///////////////////////////////////////////////////////////////////////////////
 151 #include <stdlib.h>
 152
 153 #include <TMath.h>
 154
 155 #include "AliTPCv2.h"
 156 #include "AliTPCDigitsArray.h"
 157 #include "AliRun.h"
 158 #include "AliConst.h"
 159 #include "AliPDG.h"
 160 #include "AliTPCParam.h"
 161 #include "AliTPCParamSR.h"
 162 #include "AliTPCTrackHitsV2.h"
 163 #include "TLorentzVector.h"
 164
 165
 166 ClassImp(AliTPCv2)
 167
 168 //_____________________________________________________________________________
 169 AliTPCv2::AliTPCv2(const char *name, const char *title) :
 170   AliTPC(name, title)
 171 {
 172   //
 173   // Standard constructor for Time Projection Chamber version 2
 174   //
 175   fIdSens=0;
 176   fIdLSec=0;
 177   fIdUSec=0;
 178
 179   SetBufferSize(128000);
 180
 181   SetGasMixt(2,20,10,-1,0.9,0.1,0.); // Ne-CO2 90-10
 182
 183   // Default sectors
 184
 185   SetSecAL(4);
 186   SetSecAU(4);
 187   SetSecLows(1,  2,  3, 19, 20, 21);
 188   SetSecUps(37, 38, 39, 37+18, 38+18, 39+18, -1, -1, -1, -1, -1, -1);
 189   SetSens(1); // sensitive strips set
 190
 191   if (fTPCParam)
 192      fTPCParam->Write(fTPCParam->GetTitle());
 193 }
 194
 195 //_____________________________________________________________________________
 196 void AliTPCv2::CreateGeometry()
 197 {
 198   //
 199   // Create the geometry of Time Projection Chamber version 2
 200   //
 201   //Begin_Html
 202   /*
 203     <img src="picts/AliTPC.gif">
 204   */
 205   //End_Html
 206   //Begin_Html
 207   /*
 208     <img src="picts/AliTPCv2Tree.gif">
 209   */
 210   //End_Html
 211
 212
 213   Int_t *idtmed = fIdtmed->GetArray();
 214
 215   Float_t dm[50];
 216   Int_t idrotm[120];
 217
 218   Int_t nRotMat = 0;
 219
 220   Int_t i,ifl1=0;
 221
 222   // number of sectors
 223
 224   Int_t nInnerSector = fTPCParam->GetNInnerSector()/2;
 225   Int_t nOuterSector = fTPCParam->GetNOuterSector()/2;
 226
 227   // ---------------------------------------------------
 228   //        sector specification check
 229   // ---------------------------------------------------
 230   if (fSecAL >= 0) {
 231     ifl1 = 0;
 232
 233     for (i = 0; i < 6; ++i) {
 234       if (fSecLows[i] >= 0 && fSecLows[i] < 2*nInnerSector) {
 235         ifl1 = 1;
 236         printf("%s: *** SECTOR %d selected\n",ClassName(),fSecLows[i]);
 237       }
 238     }
 239
 240   } else {
 241     printf("%s: *** ALL LOWER SECTORS SELECTED ***\n",ClassName());
 242     ifl1 = 1;
 243   }
 244
 245   if (ifl1 == 0) {
 246     printf("%s: *** ERROR: AT LEAST ONE LOWER SECTOR MUST BE SPECIFIED ***\n",ClassName());
 247     printf("%s: !!! PROGRAM STOPPED !!!\n",ClassName());
 248     exit(1);
 249   }
 250
 251   if (fSecAU >= 0) {
 252
 253     for (i = 0; i < 12; ++i) {
 254       if (fSecUps[i] > 2*nInnerSector-1 &&
 255           fSecUps[i] < 2*(nInnerSector+nOuterSector)) {
 256         printf("%s: *** SECTOR %d selected\n",ClassName(),fSecUps[i]);
 257       }
 258     }
 259
 260   } else {
 261     printf("%s: *** ALL UPPER SECTORS SELECTED ***\n",ClassName());
 262   }
 263
 264
 265
 266   //--------------------------------------------------------------------
 267
 268   //
 269   //  Mother volume TPC (Air) - all volumes will be positioned in it
 270   //
 271
 272   dm[0]=0.;
 273   dm[1]=360.;
 274   dm[2]=8.;
 275
 276   //
 277
 278   dm[3]=-283.7;
 279   dm[4]=65.6;
 280   dm[5]=278.;
 281
 282   //
 283
 284   dm[6]=-253.6;
 285   dm[7]=65.6;
 286   dm[8]=278.;
 287
 288   //
 289
 290   dm[9]=-73.3;
 291   dm[10]=60.9;
 292   dm[11]=278.;
 293
 294   //
 295
 296   dm[12]=-73.3;
 297   dm[13]=56.9;
 298   dm[14]=278.;
 299
 300   //
 301
 302   dm[15]=73.3;
 303   dm[16]=56.9;
 304   dm[17]=278.;
 305
 306   //
 307
 308   dm[18]=73.3;
 309   dm[19]=60.9;
 310   dm[20]=278.;
 311
 312   //
 313
 314   dm[21]=253.6;
 315   dm[22]=65.6;
 316   dm[23]=278.;
 317
 318   //
 319
 320   dm[24]=283.7;
 321   dm[25]=65.6;
 322   dm[26]=278.;
 323
 324   gMC->Gsvolu("TPC ","PCON",idtmed[0],dm,27);
 325
 326   // outer part
 327
 328   //-------------------------------------------------------------------
 329   //   Tpc Outer INsulator (CO2) - contains cont. vessel and field cage
 330   //-------------------------------------------------------------------
 331
 332   dm[0]= 0.;
 333   dm[1]= 360.;
 334   dm[2]= 6.;
 335
 336   //
 337
 338   dm[3]=-253.6;
 339   dm[4]=258.;
 340   dm[5]=275.5;
 341
 342   //
 343
 344   dm[6]=-250.6;
 345   dm[7]=258.;
 346   dm[8]=275.5;
 347
 348   //
 349
 350   dm[9]=-250.6;
 351   dm[10]=258.;
 352   dm[11]=278.;
 353
 354   //
 355
 356   dm[12]=253.6;
 357   dm[13]=258.;
 358   dm[14]=278.;
 359
 360   //
 361
 362   dm[15]=253.6;
 363   dm[16]=264.8;
 364   dm[17]=278.;
 365
 366   //
 367
 368   dm[18]=256.6;
 369   dm[19]=264.8;
 370   dm[20]=278.;
 371
 372   gMC->Gsvolu("TOIN","PCON",idtmed[3],dm,21);
 373
 374   //----------------------------------------------------------------
 375   // Tpc Outer Contaiment Vessel
 376   //  mother volume - Al, daughters - composite (sandwich)
 377   //----------------------------------------------------------------
 378
 379   dm[0]=0.;
 380   dm[1]=360.;
 381   dm[2]=6.;
 382
 383   //
 384
 385   dm[3]=-250.6;
 386   dm[4]=270.4;
 387   dm[5]=278.;
 388
 389   //
 390
 391   dm[6]=-247.6;
 392   dm[7]=270.4;
 393   dm[8]=278.;
 394
 395   //
 396
 397   dm[9]=-247.6;
 398   dm[10]=274.8124;
 399   dm[11]=278.;
 400
 401   //
 402
 403   dm[12]=253.6;
 404   dm[13]=274.8124;
 405   dm[14]=278.;
 406
 407   //
 408
 409   dm[15]=253.6;
 410   dm[16]=264.8;
 411   dm[17]=278.;
 412
 413   //
 414
 415   dm[18]=256.6;
 416   dm[19]=264.8;
 417   dm[20]=278.;
 418
 419   gMC->Gsvolu("TOCV","PCON",idtmed[4],dm,21);
 420
 421   // Daughter volumes - sandwich
 422
 423   // Tpc SAndwich 1 - Al
 424
 425   dm[0]=274.8124;
 426   dm[1]=278.;
 427   dm[2]=252.1;
 428
 429   gMC->Gsvolu("TSA1","TUBE",idtmed[4],dm,3);
 430
 431   // Tpc SAndwich 2 - epoxy glue (I use Lexan)
 432
 433   dm[0] += 5.e-3;
 434   dm[1] -= 5.e-3;
 435
 436   gMC->Gsvolu("TSA2","TUBE",idtmed[14],dm,3);
 437
 438   // Tpc SAndwich 3 - Tedlar
 439
 440   dm[0] += 0.01;
 441   dm[1] -= 0.01;
 442
 443   gMC->Gsvolu("TSA3","TUBE",idtmed[9],dm,3);
 444
 445
 446   // Tpc SAndwich 4 - fiber glass (G10)
 447
 448   dm[0] += 3.8e-3;
 449   dm[1] -= 3.8e-3;
 450
 451   gMC->Gsvolu("TSA4","TUBE",idtmed[12],dm,3);
 452
 453   // Tpc SAndwich 5 - NOMEX honeycomb
 454
 455   dm[0] += 0.075;
 456   dm[1] -= 0.075;
 457
 458   gMC->Gsvolu("TSA5","TUBE",idtmed[6],dm,3);
 459
 460   // 5->4->3->2->1->TCOV
 461
 462
 463   gMC->Gspos("TSA5",1,"TSA4",0.,0.,0.,0,"ONLY");
 464   gMC->Gspos("TSA4",1,"TSA3",0.,0.,0.,0,"ONLY");
 465   gMC->Gspos("TSA3",1,"TSA2",0.,0.,0.,0,"ONLY");
 466   gMC->Gspos("TSA2",1,"TSA1",0.,0.,0.,0,"ONLY");
 467
 468   gMC->Gspos("TSA1",1,"TOCV",0.,0.,3.,0,"ONLY");
 469
 470   // TCOV-> TOIN
 471
 472   gMC->Gspos("TOCV",1,"TOIN",0.,0.,0.,0,"ONLY");
 473
 474   //-------------------------------------------------------
 475   //  Tpc Outer Field Cage
 476   //  mother volume - Al, daughters - composite (sandwich)
 477   //-------------------------------------------------------
 478
 479   dm[0]=0.;
 480   dm[1]=360.;
 481   dm[2]=6.;
 482
 483   //
 484
 485   dm[3]=-253.6;
 486   dm[4]=258.;
 487   dm[5]=275.5;
 488
 489   //
 490
 491   dm[6]=-250.6;
 492   dm[7]=258.;
 493   dm[8]=275.5;
 494
 495   //
 496
 497   dm[9]=-250.6;
 498   dm[10]=258.;
 499   dm[11]=260.0476;
 500
 501   //
 502
 503   dm[12]=250.6;
 504   dm[13]=258.;
 505   dm[14]=260.0476;
 506
 507   //
 508
 509   dm[15]=250.6;
 510   dm[16]=258.;
 511   dm[17]=275.5;
 512
 513   //
 514
 515   dm[18]=253.6;
 516   dm[19]=258.;
 517   dm[20]=275.5;
 518
 519   gMC->Gsvolu("TOFC","PCON",idtmed[4],dm,21);
 520
 521   // Daughter volumes
 522
 523   // Tpc SAndwich 6 - Tedlar
 524
 525   dm[0]= 258.;
 526   dm[1]= 260.0476;
 527   dm[2]= 252.1;
 528
 529   gMC->Gsvolu("TSA6","TUBE",idtmed[9],dm,3);
 530
 531   // Tpc SAndwich 7 - fiber glass
 532
 533   dm[0] += 3.8e-3;
 534   dm[1] -= 3.8e-3;
 535
 536   gMC->Gsvolu("TSA7","TUBE",idtmed[12],dm,3);
 537
 538
 539   // Tpc SAndwich 8 - NOMEX
 540
 541   dm[0] += 0.02;
 542   dm[1] -= 0.02;
 543
 544   gMC->Gsvolu("TSA8","TUBE",idtmed[6],dm,3);
 545
 546   // 8->7->6->TOFC
 547
 548   gMC->Gspos("TSA8",1,"TSA7",0.,0.,0.,0,"ONLY");
 549   gMC->Gspos("TSA7",1,"TSA6",0.,0.,0.,0,"ONLY");
 550   gMC->Gspos("TSA6",1,"TOFC",0.,0.,0.,0,"ONLY");
 551
 552   // TOFC->TOIN
 553
 554   gMC->Gspos("TOFC",1,"TOIN",0.,0.,0.,0,"ONLY");
 555
 556   // TOIN->TPC
 557
 558   gMC->Gspos("TOIN",1,"TPC ",0.,0.,0.,0,"ONLY");
 559
 560   // inner part
 561
 562   //--------------------------------------------------------------------
 563   // Tpc Inner INsulator (CO2) - inner f.c. will be placed there
 564   // Inner containment vessel will be placed directly in the TPC
 565   //--------------------------------------------------------------------
 566
 567   dm[0]=0.;
 568   dm[1]=360.;
 569   dm[2]=4.;
 570
 571   //
 572
 573   dm[3]=-253.6;
 574   dm[4]=65.9;
 575   dm[5]=79.2;
 576
 577   //
 578
 579   dm[6]=-73.3;
 580   dm[7]=61.2;
 581   dm[8]=79.2;
 582
 583   //
 584
 585   dm[9]=73.3;
 586   dm[10]=61.2;
 587   dm[11]=79.2;
 588
 589   //
 590
 591   dm[12]=253.6;
 592   dm[13]=65.9;
 593   dm[14]=79.2;
 594
 595   gMC->Gsvolu("TIIN","PCON",idtmed[3],dm,15);
 596
 597   // the middle part of the F.C. is thinner - carve out the strip - Ne-CO2
 598
 599   dm[0]=79.16;
 600   dm[1]=79.2;
 601   dm[2]=88.;
 602
 603   gMC->Gsvolu("TII1","TUBE",idtmed[1],dm,3);
 604
 605   gMC->Gspos("TII1",1,"TIIN",0.,0.,0.,0,"ONLY");
 606
 607   //-----------------------------------------------------
 608   // Tpc Inner Field Cage
 609   // mother volume - Al, daughters - composite (sandwich)
 610   //------------------------------------------------------
 611
 612   dm[0]=0.;
 613   dm[1]=360.;
 614   dm[2]=10.;
 615
 616   //
 617
 618   dm[3]=-253.6;
 619   dm[4]=70.3;
 620   dm[5]=79.2;
 621
 622   //
 623
 624   dm[6]=-250.6;
 625   dm[7]=70.3;
 626   dm[8]=79.2;
 627
 628   //
 629
 630   dm[9]=-250.6;
 631   dm[10]=77.0524;
 632   dm[11]=79.2;
 633
 634   //
 635
 636   dm[12]=-88.;
 637   dm[13]=77.0524;
 638   dm[14]=79.2;
 639
 640   //
 641
 642   dm[15]=-88.;
 643   dm[16]=77.0924;
 644   dm[17]=79.16;
 645
 646   //
 647
 648   dm[18]=88.;
 649   dm[19]=77.0924;
 650   dm[20]=79.16;
 651
 652   //
 653
 654   dm[21]=88.;
 655   dm[22]=77.0524;
 656   dm[23]=79.2;
 657
 658   //
 659
 660   dm[24]=250.6;
 661   dm[25]=77.0524;
 662   dm[26]=79.2;
 663
 664   //
 665
 666   dm[27]=250.6;
 667   dm[28]=70.3;
 668   dm[29]=79.2;
 669
 670   //
 671
 672   dm[30]=253.6;
 673   dm[31]=70.3;
 674   dm[32]=79.2;
 675
 676   gMC->Gsvolu("TIFC","PCON",idtmed[4],dm,33);
 677
 678   // daughter volumes - central part
 679
 680   // Tpc Sandwich 9 -Tedlar
 681
 682   dm[0]=77.0924;
 683   dm[1]=79.16;
 684   dm[2]=88.;
 685
 686   gMC->Gsvolu("TSA9","TUBE",idtmed[9],dm,3);
 687
 688   // Tpc Sandwich 10 - fiber glass (G10)
 689
 690   dm[0] += 3.8e-3;
 691   dm[1] -= 3.8e-3;
 692
 693   gMC->Gsvolu("TS10","TUBE",idtmed[12],dm,3);
 694
 695   // Tpc Sandwich 11 - NOMEX
 696
 697   dm[0] += 0.03;
 698   dm[1] -= 0.03;
 699
 700   gMC->Gsvolu("TS11","TUBE",idtmed[6],dm,3);
 701
 702   // 11->10->9->TIFC
 703
 704   gMC->Gspos("TS11",1,"TS10",0.,0.,0.,0,"ONLY");
 705   gMC->Gspos("TS10",1,"TSA9",0.,0.,0.,0,"ONLY");
 706
 707   gMC->Gspos("TSA9",1,"TIFC",0.,0.,0.,0,"ONLY");
 708
 709   // daughter volumes - outer parts (reinforced)
 710
 711   // Tpc Sandwich 12 -Tedlar
 712
 713   dm[0]=77.0524;
 714   dm[1]=79.2;
 715   dm[2]=82.05;
 716
 717   gMC->Gsvolu("TS12","TUBE",idtmed[9],dm,3);
 718
 719   // Tpc Sandwich 13 - fiber glass (G10)
 720
 721   dm[0] += 3.8e-3;
 722   dm[1] -= 3.8e-3;
 723
 724   gMC->Gsvolu("TS13","TUBE",idtmed[12],dm,3);
 725
 726   // Tpc Sandwich 14 - NOMEX
 727
 728   dm[0] += 0.07;
 729   dm[1] -= 0.07;
 730
 731   gMC->Gsvolu("TS14","TUBE",idtmed[6],dm,3);
 732
 733   // 14->13->12->TIFC
 734
 735   gMC->Gspos("TS14",1,"TS13",0.,0.,0.,0,"ONLY");
 736   gMC->Gspos("TS13",1,"TS12",0.,0.,0.,0,"ONLY");
 737
 738   gMC->Gspos("TS12",1,"TIFC",0.,0.,170.05,0,"ONLY");
 739   gMC->Gspos("TS12",2,"TIFC",0.,0.,-170.05,0,"ONLY");
 740
 741   // place this inside the inner insulator
 742
 743   gMC->Gspos("TIFC",1,"TIIN",0.,0.,0.,0,"ONLY");
 744
 745   // and now in the TPC...
 746
 747   gMC->Gspos("TIIN",1,"TPC ",0.,0.,0.,0,"ONLY");
 748
 749   //---------------------------------------------------------
 750   // Tpc Inner Containment vessel - Cones
 751   //---------------------------------------------------------
 752
 753   dm[0]=0.;
 754   dm[1]=360.;
 755   dm[2]=8.;
 756
 757   //
 758
 759   dm[3]=71.8;
 760   dm[4]=56.9;
 761   dm[5]=59.4;
 762
 763   //
 764
 765   dm[6]=73.;
 766   dm[7]=56.9;
 767   dm[8]=59.4;
 768
 769   //
 770
 771   dm[9]=73.;
 772   dm[10]=56.9;
 773   dm[11]=61.2;
 774
 775   //
 776
 777   dm[12]=73.3;
 778   dm[13]=56.9;
 779   dm[14]=61.2;
 780
 781   //
 782
 783   dm[15]=73.3;
 784   dm[16]=60.9;
 785   dm[17]=61.2;
 786
 787   //
 788
 789   dm[18]=253.6;
 790   dm[19]=65.6;
 791   dm[20]=65.9;
 792
 793   //
 794
 795   dm[21]=253.6;
 796   dm[22]=65.6;
 797   dm[23]=74.6;
 798
 799   //
 800
 801   dm[24]=256.6;
 802   dm[25]=65.6;
 803   dm[26]=74.6;
 804
 805   gMC->Gsvolu("TICC","PCON",idtmed[4],dm,27);
 806
 807   Float_t phi1,phi2,phi3,theta1,theta2,theta3; // rotation angles
 808
 809   // reflection matrix
 810
 811   theta1 = 90.;
 812   phi1   = 0.;
 813   theta2 = 90.;
 814   phi2   = 270.;
 815   theta3 = 180.;
 816   phi3   = 0.;
 817
 818   AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
 819
 820   gMC->Gspos("TICC",1,"TPC ",0.,0.,0.,0,"ONLY");
 821   gMC->Gspos("TICC",2,"TPC ",0.,0.,0.,idrotm[nRotMat],"ONLY");
 822
 823
 824   //---------------------------------------------------------
 825   // Tpc Inner Containment vessel - Middle part -Al
 826   //---------------------------------------------------------
 827
 828   dm[0]=0.;
 829   dm[1]=360.;
 830   dm[2]=6.;
 831
 832   //
 833
 834   dm[3]=-71.6;
 835   dm[4]=60.2;
 836   dm[5]=61.2;
 837
 838   //
 839
 840   dm[6]=-69.1;
 841   dm[7]=60.2;
 842   dm[8]=61.2;
 843
 844   //
 845
 846   dm[9]=-69.1;
 847   dm[10]=60.6224;
 848   dm[11]=61.2;
 849
 850   //
 851
 852   dm[12]=69.1;
 853   dm[13]=60.6224;
 854   dm[14]=61.2;
 855
 856   //
 857
 858   dm[15]=69.1;
 859   dm[16]=60.2;
 860   dm[17]=61.2;
 861
 862   //
 863
 864   dm[18]=71.6;
 865   dm[19]=60.2;
 866   dm[20]=61.2;
 867
 868   gMC->Gsvolu("TICM","PCON",idtmed[4],dm,21);
 869
 870   // Tpc Sandwich 15 - Al
 871
 872   dm[0]=60.6224;
 873   dm[1]=61.2;
 874   dm[2]=70.1;
 875
 876   gMC->Gsvolu("TS15","TUBE",idtmed[4],dm,3);
 877
 878   // Tpc Sandwich 16 -  epoxy glue
 879
 880   dm[0] += 5.e-3;
 881   dm[1] -= 5.e-3;
 882
 883   gMC->Gsvolu("TS16","TUBE",idtmed[14],dm,3);
 884
 885   // Tpc Sandwich 17 - Tedlar
 886
 887   dm[0] += 0.01;
 888   dm[1] -= 0.01;
 889
 890   gMC->Gsvolu("TS17","TUBE",idtmed[9],dm,3);
 891
 892   // Tpc Sandwich 18 - carbon fiber
 893
 894   dm[0] += 3.8e-3;
 895   dm[1] -= 3.8e-3;
 896
 897   gMC->Gsvolu("TS18","TUBE",idtmed[15],dm,3);
 898
 899   // Tpc Sandwich 19 - Nomex
 900
 901   dm[0] += 0.02;
 902   dm[1] -= 0.02;
 903
 904   gMC->Gsvolu("TS19","TUBE",idtmed[6],dm,3);
 905
 906   // 19->18->17->16->15-> TICM
 907
 908   gMC->Gspos("TS19",1,"TS18",0.,0.,0.,0,"ONLY");
 909   gMC->Gspos("TS18",1,"TS17",0.,0.,0.,0,"ONLY");
 910   gMC->Gspos("TS17",1,"TS16",0.,0.,0.,0,"ONLY");
 911   gMC->Gspos("TS16",1,"TS15",0.,0.,0.,0,"ONLY");
 912
 913   gMC->Gspos("TS15",1,"TICM ",0.,0.,0.,0,"ONLY");
 914
 915
 916   // TPc inner cont. vessel Joints
 917
 918   dm[0]=60.2;
 919   dm[1]=61.2;
 920   dm[2]=0.5;
 921
 922   gMC->Gsvolu("TPJ1","TUBE",idtmed[4],dm,3);
 923
 924   gMC->Gspos("TPJ1",1,"TPC ",0.,0.,72.3,0,"ONLY");
 925   gMC->Gspos("TPJ1",2,"TPC ",0.,0.,-72.3,0,"ONLY");
 926
 927   //
 928
 929   dm[0]=0.;
 930   dm[1]=360.;
 931   dm[2]=4.;
 932
 933   //
 934
 935   dm[3]=70.8;
 936   dm[4]=58.4;
 937   dm[5]=60.1;
 938
 939   //
 940
 941   dm[6]=71.2;
 942   dm[7]=58.4;
 943   dm[8]=60.1;
 944
 945   //
 946
 947   dm[9]=71.2;
 948   dm[10]=58.4;
 949   dm[11]=59.4;
 950
 951   //
 952
 953   dm[12]=71.6;
 954   dm[13]=58.4;
 955   dm[14]=59.4;
 956
 957   gMC->Gsvolu("TPJ2","PCON",idtmed[4],dm,15);
 958
 959   gMC->Gspos("TPJ2",1,"TPC ",0.,0.,0.,0,"ONLY");
 960   gMC->Gspos("TPJ2",2,"TPC ",0.,0.,0.,idrotm[nRotMat],"ONLY");
 961
 962
 963
 964   // Tpc Inner Containment vessel Seal (Viton, I use Lexan for a time being)
 965
 966   dm[0]=58.4;
 967   dm[1]=61.2;
 968   dm[2]=0.1;
 969
 970   gMC->Gsvolu("TICS","TUBE",idtmed[14],dm,3);
 971
 972   gMC->Gspos("TICS",1,"TPC ",0.,0.,71.7,0,"ONLY");
 973   gMC->Gspos("TICS",2,"TPC ",0.,0.,-71.7,0,"ONLY");
 974
 975   // TICM -> TPC
 976
 977   gMC->Gspos("TICM",1,"TPC ",0.,0.,0.,0,"ONLY");
 978
 979   //
 980
 981   nRotMat++; // prepare for the next rotation matrix
 982
 983   //---------------------------------------------------------
 984   //  Tpc Dift Gas volume Nonsensitive (Ne-CO2 90/10)
 985   //  and its daughters (HV membrane, rods, readout chambers)
 986   //---------------------------------------------------------
 987
 988   dm[0]= 79.2;
 989   dm[1]= 258.0;
 990   dm[2]= 253.6;
 991
 992   gMC->Gsvolu("TDGN","TUBE",idtmed[1],dm,3);
 993
 994   // sector opening angles
 995
 996   Float_t innerOpenAngle = fTPCParam->GetInnerAngle();
 997   Float_t outerOpenAngle = fTPCParam->GetOuterAngle();
 998
 999   // sector angle shift
1000
1001   Float_t innerAngleShift = fTPCParam->GetInnerAngleShift();
1002
1003
1004   // All above parameters are identical for inner and outer
1005   // sectors. The distinction is kept for the historical reasons
1006   // and eventually will disappear.
1007
1008   Float_t tanAlpha = TMath::Tan(0.5*innerOpenAngle);
1009   Float_t cosAlpha = TMath::Sqrt(1.+tanAlpha*tanAlpha);
1010   Float_t space;
1011
1012   //-------------------------------------------------------------------------
1013   //   Tpc Inner Readout Chambers
1014   //-------------------------------------------------------------------------
1015
1016   dm[0]= 14.483;
1017   dm[1]= 23.3345;
1018   dm[2]= 1.6; // thickness
1019   dm[3]= 25.1;
1020
1021   gMC->Gsvolu("TIRC","TRD1",idtmed[4],dm,4);
1022
1023   // this volume will be positioned in the empty space
1024   // of the end-cap to avoid overlaps
1025
1026   dm[0]= 13.7305;
1027   dm[1]= 21.1895;
1028   dm[2]= 2.25;
1029   dm[3]= 21.15;
1030
1031   gMC->Gsvolu("TIC1","TRD1",idtmed[4],dm,4);
1032
1033
1034   //------------------------------------------------
1035   // Tpc Inner readout chamber Pad Plane
1036   //------------------------------------------------
1037
1038   dm[0]= 14.483;
1039   dm[1]= 23.3345;
1040   dm[2]= 0.5;
1041   dm[3]= 25.1;
1042
1043   gMC->Gsvolu("TIPP","TRD1",idtmed[12],dm,4);
1044
1045   //
1046
1047   dm[0] -= 1.218511934;
1048   dm[1] -= 1.218511934;
1049   dm[2] = 0.35;
1050
1051   gMC->Gsvolu("TIC3","TRD1",idtmed[1],dm,4);
1052
1053   gMC->Gspos("TIC3",1,"TIPP",0.,0.15,0.,0,"ONLY");
1054
1055   gMC->Gspos("TIPP",1,"TIRC",0.,1.1,0.,0,"ONLY");
1056
1057
1058   //----------------------------------------------
1059   // Tpc Readout Chambers Empty spaces - for both
1060   // inner and outer sectors
1061   //----------------------------------------------
1062
1063   gMC->Gsvolu("TRCE","TRD1",idtmed[0],dm,0);
1064
1065   // Inner sector - 4 spaces
1066
1067
1068   dm[3] = 4.7625;
1069   dm[0] = 12.472;
1070
1071   Float_t rr = 90.52;
1072   Float_t zz;
1073
1074   zz= -12.7875;
1075
1076   space = rr*tanAlpha-dm[0];
1077
1078   for(Int_t nsLow=0;nsLow<4;nsLow++){
1079
1080     rr += 9.525;
1081     dm[1]= rr*tanAlpha - space;
1082
1083     dm[2]=0.8;
1084
1085     gMC->Gsposp("TRCE",nsLow+1,"TIRC",0.,-0.8,zz,0,"ONLY",dm,4);
1086
1087     //
1088
1089     dm[2] = 1.2;
1090
1091     gMC->Gsposp("TRCE",nsLow+5,"TIC1",0.,1.05,zz-2.1,0,"ONLY",dm,4);
1092
1093     rr += 0.4;
1094     dm[0] = rr*tanAlpha - space;
1095     zz += (0.4+9.525);
1096
1097   }
1098
1099   dm[0]= 12.472;
1100   // dm[1] - this is the dm[1] from the previous TRCE
1101   dm[2]= 1.05;
1102   dm[3]= 19.65;
1103
1104   gMC->Gsposp("TRCE",9,"TIC1",0.,-1.2,0.,0,"ONLY",dm,4);
1105
1106   //
1107   // TPc Space for Connectors
1108   //
1109
1110   dm[0]= .3;
1111   dm[1]= .3;
1112   dm[2]= 4.5;
1113
1114   gMC->Gsvolu("TPSC","BOX ",idtmed[0],dm,3);
1115
1116   // TPC Connectors
1117
1118   dm[0]= .25;
1119   dm[1]= .15;
1120   dm[2]= 3.75;
1121
1122   gMC->Gsvolu("TPCC","BOX ",idtmed[13],dm,3);
1123
1124   gMC->Gspos("TPCC",1,"TPSC",0.,0.15,0.,0,"ONLY");
1125
1126   zz = -12.7875;
1127
1128
1129   Float_t alpha;
1130   Float_t astep;
1131
1132   // inner part of the inner sector - 2 x 20 holes
1133
1134   astep = 20.00096874/19.;
1135
1136   alpha = 10.00048437-astep;
1137
1138   Float_t x1,x2;
1139
1140     x1 = 13.31175725;
1141     x1 -= 0.996357832;
1142
1143     x2 = 15.06180253;
1144     x2 -= 1.163028812;
1145
1146   Int_t ncon;
1147
1148   for(ncon=0;ncon<20;ncon++){
1149
1150     phi1 = 0.;
1151     theta1 = 90.+alpha;
1152     phi2=90.;
1153     theta2 = 90.;
1154     phi3 = (alpha>0) ? 0. : 180.;
1155     theta3 = TMath::Abs(alpha);
1156
1157     AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
1158
1159
1160
1161     gMC->Gspos("TPSC",ncon+1,"TIRC",x1,0.3,-12.7875,idrotm[nRotMat],"ONLY");
1162     gMC->Gspos("TPSC",ncon+21,"TIRC",x2,0.3,-2.8625,idrotm[nRotMat],"ONLY");
1163
1164
1165     x1 -= 1.296357833;
1166     x2 -= 1.463028812;
1167
1168     alpha -= astep;
1169     nRotMat++;
1170
1171   }
1172
1173   // outer part of the inner sector - 2 x 25 holes
1174
1175    astep = 20.00096874/24.;
1176    alpha = 10.00048437-astep;
1177
1178    x1 = 16.81184781;
1179    x1 -= 1.016295986;
1180
1181    x2 = 18.5618931;
1182    x2 -= 1.150914854;
1183
1184   for(ncon=0;ncon<25;ncon++){
1185
1186     phi1 = 0.;
1187     theta1 = 90.+alpha;
1188     phi2=90.;
1189     theta2 = 90.;
1190     phi3 = (alpha>0) ? 0. : 180.;
1191     theta3 = TMath::Abs(alpha);
1192
1193     AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
1194
1195
1196
1197     gMC->Gspos("TPSC",ncon+41,"TIRC",x1,0.3,7.0625,idrotm[nRotMat],"ONLY");
1198     gMC->Gspos("TPSC",ncon+66,"TIRC",x2,0.3,16.9875,idrotm[nRotMat],"ONLY");
1199
1200
1201     x1 -= 1.316295986;
1202     x2 -= 1.450914854;
1203
1204     alpha -= astep;
1205     nRotMat++;
1206
1207   }
1208
1209   //--------------------------------------------------------------------------
1210   //  TPC Outer Readout Chambers
1211   //  this is NOT a final design
1212   //--------------------------------------------------------------------------
1213
1214   dm[0]= 23.3875;
1215   dm[1]= 43.524;
1216   dm[2]= 1.5; //thickness
1217   dm[3]= 57.1;
1218
1219   gMC->Gsvolu("TORC","TRD1",idtmed[4],dm,4);
1220
1221   //------------------------------------------------
1222   // Tpc Outer readout chamber Pad Plane
1223   //------------------------------------------------
1224
1225   dm[2]= 0.5;
1226
1227   gMC->Gsvolu("TOPP","TRD1",idtmed[12],dm,4);
1228
1229   dm[0] -= 1.218511934;
1230   dm[1] -= 1.218511934;
1231   dm[2] = 0.35;
1232
1233   gMC->Gsvolu("TOC3","TRD1",idtmed[1],dm,4);
1234
1235   gMC->Gspos("TOC3",1,"TOPP",0.,0.15,0.,0,"ONLY");
1236
1237   gMC->Gspos("TOPP",1,"TORC",0.,1.0,0.,0,"ONLY");
1238
1239   // empty space
1240
1241   dm[0]= 21.035;
1242   dm[1]= 38.7205;
1243   dm[2]= 0.7;
1244   dm[3]= 50.15;
1245
1246   gMC->Gsposp("TRCE",10,"TORC",0.,-0.8,-2.15,0,"ONLY",dm,4);
1247
1248   dm[0]= 22.2935;
1249   dm[1]= 40.5085;
1250   dm[2]= 2.25;
1251   dm[3]= 51.65;
1252
1253   gMC->Gsvolu("TOC1","TRD1",idtmed[4],dm,4);
1254
1255   dm[0]= 21.35;
1256   dm[1]= 38.7205;
1257   dm[2]= 2.25;
1258   dm[3]= 50.15;
1259
1260   gMC->Gsposp("TRCE",11,"TOC1",0.,0.,0.,0,"ONLY",dm,4);
1261
1262   //-----------------------------------------------
1263   // Tpc Services Support Wheel
1264   //-----------------------------------------------
1265
1266   dm[0]=0.;
1267   dm[1]=360.;
1268   dm[2]=18.;
1269   dm[3]=2.;
1270
1271   dm[4]= -5.;
1272   dm[5]= 77.017;
1273   dm[6]= 255.267;
1274
1275   dm[7]= 5.;
1276   dm[8]= dm[5];
1277   dm[9]= dm[6];
1278
1279   gMC->Gsvolu("TSSW","PGON",idtmed[4],dm,10);
1280
1281   // Tpc Services Wheel Cover
1282
1283   dm[4]= -0.5;
1284   dm[7]= 0.5;
1285
1286   gMC->Gsvolu("TSWC","PGON",idtmed[4],dm,10);
1287
1288   // Tpc Service wheel Cover Empty space
1289
1290   dm[0]= 10.99;
1291   dm[1]= 39.599;
1292   dm[2]= .5;
1293   dm[3]= 81.125;
1294
1295   gMC->Gsvolu("TSCE","TRD1",idtmed[0],dm,4);
1296
1297   // Tpc services Wheel Empty Spaces
1298
1299   dm[0]= 13.18017507;
1300   dm[1]= 44.61045938;
1301   dm[2]= 4.;
1302   dm[3]= 89.125;
1303
1304   gMC->Gsvolu("TWES","TRD1",idtmed[0],dm,4);
1305
1306   // Tpc Services Wheel Bars
1307
1308   gMC->Gsvolu("TSWB","TRD1",idtmed[4],dm,0);
1309
1310   // bars-> TWES
1311
1312   dm[2]= 4.;
1313   dm[3]= .4;
1314
1315   dm[0]= 13.8149522;
1316   dm[1]= 13.95601379;
1317
1318   gMC->Gsposp("TSWB",1,"TWES",0.,0.,-85.125,0,"ONLY",dm,4);
1319
1320   dm[0]= 43.83462067;
1321   dm[1]= 43.97568225;
1322
1323   gMC->Gsposp("TSWB",2,"TWES",0.,0.,85.125,0,"ONLY",dm,4);
1324
1325   // TPc ELectronics - right now 30% X0 Si
1326
1327   dm[0]= 14.03813696;
1328   dm[1]= 43.3524075;
1329   dm[2]= 1.404;
1330   dm[3]= 83.125;
1331
1332   gMC->Gsvolu("TPEL","TRD1",idtmed[11],dm,4);
1333   gMC->Gspos("TPEL",1,"TWES",0.,0.,0.,0,"ONLY");
1334
1335   //--------------------------------------------------------------------------
1336   //  End caps
1337   //--------------------------------------------------------------------------
1338
1339   // TPc Main Wheel - Al
1340
1341   dm[0]= 74.9;
1342   dm[1]= 264.4;
1343   dm[2]= 3.0;
1344
1345   gMC->Gsvolu("TPMW","TUBE",idtmed[4],dm,3);
1346
1347   //--------------------------------------------------------------------------
1348   //  Tpc Empty Space for the Readout chambers
1349   //--------------------------------------------------------------------------
1350
1351   Float_t rLow= 86.2;
1352   Float_t rUp= 243.5;
1353   Float_t dR = 0.5*(rUp-rLow);
1354
1355   space= 1.5/cosAlpha; // wheel ribs are 3.0 cm wide
1356
1357   dm[0]= rLow*tanAlpha-space;
1358   dm[1]= rUp*tanAlpha-space;
1359   dm[2] = 3.0;
1360   dm[3]= dR;
1361
1362   gMC->Gsvolu("TESR","TRD1",idtmed[0],dm,4);
1363
1364   // TIC1->TESR
1365
1366   gMC->Gspos("TIC1",1,"TESR",0.,0.75,-dR+23.97,0,"ONLY");
1367
1368   // TOC1->TESR
1369
1370   gMC->Gspos("TOC1",1,"TESR",0.,0.75,dR-55.02,0,"ONLY");
1371
1372   // Tpc Empty Space Bars - Al (daughters of TESR)
1373
1374   Float_t zBar;
1375
1376   gMC->Gsvolu("TESB","TRD1",idtmed[4],dm,0);
1377
1378   // lower bar
1379
1380   dm[0]= rLow*tanAlpha-space;
1381   dm[1]= 88.7*tanAlpha-space;
1382   dm[2]= 2.25;
1383   dm[3]= 1.275;
1384
1385   zBar = -dR+dm[3];
1386
1387   gMC->Gsposp("TESB",1,"TESR",0.,0.75,zBar,0,"ONLY",dm,4);
1388
1389   // middle bar
1390
1391   dm[0]= 131.65*tanAlpha-space;
1392   dm[1]= 136.5*tanAlpha-space;
1393   dm[3]= 2.425;
1394
1395   zBar = -dR +131.65+dm[3]-rLow;
1396
1397   gMC->Gsposp("TESB",2,"TESR",0.,0.75,zBar,0,"ONLY",dm,4);
1398
1399   // upper bar
1400
1401   dm[0]= 240.4*tanAlpha-space;
1402   dm[1]= rUp*tanAlpha-space;
1403   dm[3]= 1.55;
1404
1405   zBar = dR-dm[3];
1406
1407   gMC->Gsposp("TESB",3,"TESR",0.,0.75,zBar,0,"ONLY",dm,4);
1408
1409   //------------------------------------------------------
1410   //  TPc Lower "S" Sectors
1411   //------------------------------------------------------
1412
1413
1414   Float_t inSecLowEdge = fTPCParam->GetInnerRadiusLow();
1415   Float_t inSecUpEdge =  fTPCParam->GetInnerRadiusUp();
1416
1417   dm[0] = inSecLowEdge*TMath::Tan(0.5*innerOpenAngle)-0.01;
1418   dm[1] = inSecUpEdge*TMath::Tan(0.5*innerOpenAngle)-0.01;
1419   dm[2] = 0.5*(250. - 5.e-3);
1420   dm[3] = 0.5*(inSecUpEdge-inSecLowEdge);
1421
1422   gMC->Gsvolu("TPLS", "TRD1", idtmed[2], dm, 4); // sensitive
1423
1424
1425   //----------------------------------------------------------
1426   //  TPc Upper Sectors
1427   //----------------------------------------------------------
1428
1429   Float_t ouSecLowEdge = fTPCParam->GetOuterRadiusLow();
1430   Float_t ouSecUpEdge = fTPCParam->GetOuterRadiusUp();
1431
1432   dm[0] = ouSecLowEdge*TMath::Tan(0.5*outerOpenAngle)-0.01;
1433   dm[1] = ouSecUpEdge*TMath::Tan(0.5*outerOpenAngle)-0.01;
1434   dm[2] = 0.5*(250. - 5.e-3);
1435   dm[3] = 0.5*(ouSecUpEdge-ouSecLowEdge);
1436
1437   gMC->Gsvolu("TPUS", "TRD1", idtmed[2], dm, 4); // sensitive
1438
1439
1440
1441   // sensitive strips
1442
1443     gMC->Gsvolu("TPSS","TRD1",idtmed[2],dm,0); // sensitive
1444
1445     Int_t nofStrips,nstr;
1446     Float_t r1,r2,zs;
1447     Float_t stripThick = 0.01; // 100 microns
1448     Float_t deadSpace;
1449
1450     // inner sector
1451
1452
1453     // if all lower sectors selected define only 1 strip
1454
1455     nofStrips=((fSecAL <0)||(fSecAL>=0 && fSens<0)) ? 1 : fTPCParam->GetNRowLow();
1456     deadSpace = fTPCParam->GetInnerWireMount();
1457
1458     dm[2] = 0.5*(250. - 5.e-3);
1459     dm[3] = 0.5 * stripThick;
1460
1461     for(nstr=0;nstr<nofStrips;nstr++){
1462
1463       r1 = fTPCParam->GetPadRowRadiiLow(nstr);
1464       r2 = r1 + stripThick;
1465       dm[0] = r1 * TMath::Tan(0.5*innerOpenAngle) - deadSpace;
1466       dm[1] = r2 * TMath::Tan(0.5*innerOpenAngle) - deadSpace;
1467       zs = -inSecLowEdge -0.5*(inSecUpEdge-inSecLowEdge);
1468       zs += r1;
1469       zs += dm[3];
1470
1471       gMC->Gsposp("TPSS", nstr+1, "TPLS", 0., 0., zs, 0, "ONLY", dm, 4);
1472
1473
1474     }
1475
1476     // strips only if several upper sectors selected end fSens > 0
1477
1478     if(fSecAU >=0 && fSens >0){
1479
1480     Int_t nsSave = nofStrips;
1481
1482     // outer sector
1483
1484     nofStrips = fTPCParam->GetNRowUp();
1485     deadSpace = fTPCParam->GetOuterWireMount();
1486
1487     dm[2] = 0.5*(250. - 5.e-3);
1488     dm[3] = 0.5 * stripThick;
1489
1490
1491     for(nstr=0;nstr<nofStrips;nstr++){
1492
1493       r1 = fTPCParam->GetPadRowRadiiUp(nstr);
1494       r2 = r1 + stripThick;
1495       dm[0] = r1 * TMath::Tan(0.5*outerOpenAngle) - deadSpace;
1496       dm[1] = r2 * TMath::Tan(0.5*outerOpenAngle) - deadSpace;
1497       zs = -ouSecLowEdge -0.5*(ouSecUpEdge-ouSecLowEdge);
1498       zs += r1;
1499       zs += dm[3];
1500
1501       gMC->Gsposp("TPSS", nstr+1+nsSave, "TPUS", 0., 0., zs, 0, "ONLY", dm, 4);
1502
1503      }
1504     }
1505
1506
1507   //-------------------------------------------------------
1508   //  positioning of the empty spaces into the main wheel
1509   //  and readout chambers and sectors into the drift gas
1510   //-------------------------------------------------------
1511
1512   Float_t rCenter,xc,yc;
1513   Float_t rInner,rOuter; // center of the inner and outer chamber
1514
1515   rCenter = rLow+dR;
1516
1517   rInner = 108.07;
1518   rOuter = 190.68;
1519
1520
1521   for(Int_t ns=0; ns<nInnerSector;ns++){
1522
1523     phi1 = ns * innerOpenAngle + innerAngleShift;
1524     phi1 *= kRaddeg; // in degrees
1525
1526     phi1 = (Float_t)TMath::Nint(phi1) + 270.;
1527
1528     if (phi1 > 360.) phi1 -= 360.;
1529
1530     theta1 = 90.;
1531     phi2   = 90.;
1532     theta2 = 180.;
1533     phi3   = ns * innerOpenAngle + innerAngleShift;
1534     phi3 *= kRaddeg; // in degrees
1535
1536     phi3 = (Float_t)TMath::Nint(phi3);
1537
1538     if(phi3 > 360.) phi3 -= 360.;
1539
1540     theta3 = 90.;
1541
1542     // "holes"->End plate
1543
1544     xc = rCenter*TMath::Cos(phi3*kDegrad);
1545     yc = rCenter*TMath::Sin(phi3*kDegrad);
1546
1547     AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
1548
1549     gMC->Gspos("TESR",ns+1,"TPMW",xc,yc,0.,idrotm[nRotMat],"ONLY");
1550
1551     // TSCE->TSWC (services wheel volumes)
1552
1553     xc = 166.142*TMath::Cos(phi3*kDegrad);
1554     yc = 166.142*TMath::Sin(phi3*kDegrad);
1555
1556     gMC->Gspos("TSCE",ns+1,"TSWC",xc,yc,0.,idrotm[nRotMat],"ONLY");
1557     gMC->Gspos("TWES",ns+1,"TSSW",xc,yc,0.,idrotm[nRotMat],"ONLY");
1558
1559
1560     // readout chambers->TDGN (drift gas)
1561
1562     xc = rInner*TMath::Cos(phi3*kDegrad);
1563     yc = rInner*TMath::Sin(phi3*kDegrad);
1564
1565     gMC->Gspos("TIRC",ns+1,"TDGN",xc,yc,252.,idrotm[nRotMat],"ONLY");
1566
1567     // here lower sectors
1568
1569     if(fSecAL <0){
1570
1571       // all lower sectors are positioned
1572
1573       gMC->Gspos("TPLS",ns+1,"TDGN",xc,yc,125.0025,idrotm[nRotMat],"ONLY");
1574       gMC->
1575         Gspos("TPLS",ns+nInnerSector+1,"TDGN",xc,yc,-125.0025,idrotm[nRotMat],"ONLY");
1576     }
1577     else{
1578
1579       // only selected sectors are positioned (up to 6 sectors)
1580
1581       for(Int_t sel=0;sel<6;sel++){
1582
1583         if(fSecLows[sel] == ns){
1584           gMC->Gspos("TPLS",ns+1,"TDGN",xc,yc,125.0025,idrotm[nRotMat],"ONLY");
1585         }
1586         else if(fSecLows[sel] == ns+nInnerSector){
1587          gMC->
1588          Gspos("TPLS",ns+nInnerSector+1,"TDGN",xc,yc,-125.0025,idrotm[nRotMat],"ONLY");
1589         }
1590       }
1591     } // lower sectors finished
1592
1593
1594     xc = rOuter*TMath::Cos(phi3*kDegrad);
1595     yc = rOuter*TMath::Sin(phi3*kDegrad);
1596
1597     gMC->Gspos("TORC",ns+1,"TDGN",xc,yc,252.1,idrotm[nRotMat],"ONLY");
1598
1599     // here upper sectors
1600
1601     if(fSecAU <0){
1602
1603       // all upper sectors
1604
1605       gMC->Gspos("TPUS",ns+1,"TDGN",xc,yc,125.0025,idrotm[nRotMat],"ONLY");
1606       gMC->
1607         Gspos("TPUS",ns+nOuterSector+1,"TDGN",xc,yc,-125.0025,idrotm[nRotMat],"ONLY");
1608     }
1609     else{
1610
1611       // only selected sectors (up to 12)
1612
1613       for(Int_t sel=0;sel<12;sel++){
1614         if(fSecUps[sel] == ns+2*nInnerSector){
1615           gMC->Gspos("TPUS",ns+1,"TDGN",xc,yc,125.0025,idrotm[nRotMat],"ONLY");
1616         }
1617         else if(fSecUps[sel] == ns+2*nInnerSector+nOuterSector){
1618          gMC->
1619           Gspos("TPUS",ns+nOuterSector+1,"TDGN",xc,yc,-125.0025,idrotm[nRotMat],"ONLY");
1620         }
1621       }
1622     } // upper sectors finished
1623
1624
1625     nRotMat++;
1626
1627     theta2 = 0.; // reflection
1628
1629     AliMatrix(idrotm[nRotMat], theta1, phi1, theta2, phi2, theta3, phi3);
1630
1631     xc = rInner*TMath::Cos(phi3*kDegrad);
1632     yc = rInner*TMath::Sin(phi3*kDegrad);
1633
1634     gMC->Gspos("TIRC",ns+nInnerSector+1,"TDGN",xc,yc,-252.,idrotm[nRotMat],"ONLY");
1635
1636     xc = rOuter*TMath::Cos(phi3*kDegrad);
1637     yc = rOuter*TMath::Sin(phi3*kDegrad);
1638
1639     gMC->Gspos("TORC",ns+nOuterSector+1,"TDGN",xc,yc,-252.1,idrotm[nRotMat],"ONLY");
1640
1641     nRotMat++;
1642
1643   }
1644   // TPMW->TPC
1645
1646   gMC->Gspos("TPMW",1,"TPC ",0.,0.,256.6,0,"ONLY");
1647   gMC->Gspos("TPMW",2,"TPC ",0.,0.,-256.6,idrotm[0],"ONLY");
1648
1649   //---------------------------------------------------------
1650   //  Tpc High Voltage Membrane - 100 microns of mylar
1651   //---------------------------------------------------------
1652
1653   dm[0]=82.8;
1654   dm[1]=252.;
1655   dm[2]=0.005;
1656
1657   gMC->Gsvolu("THVM","TUBE",idtmed[8],dm,3);
1658
1659   gMC->Gspos("THVM",1,"TDGN",0.,0.,0.,0,"ONLY");
1660
1661   // Tpc High Voltage membrane Holders
1662
1663   gMC->Gsvolu("THVH","TUBE",idtmed[4],dm,0);
1664
1665
1666
1667   // inner
1668
1669   dm[0]=79.3;
1670   dm[1]=82.8;
1671   dm[2]=0.2;
1672
1673   gMC->Gsposp("THVH",1,"TDGN",0.,0.,0.,0,"ONLY",dm,3);
1674
1675   // outer
1676
1677   dm[0]= 252.;
1678   dm[1]= 257.9;
1679   dm[2]= 0.4;
1680
1681   gMC->Gsposp("THVH",2,"TDGN",0.,0.,0.,0,"ONLY",dm,3);
1682
1683   //----------------------------------------------------------
1684   // TPc Support Rods - MAKROLON
1685   //----------------------------------------------------------
1686
1687   dm[0]= 0.9;
1688   dm[1]= 1.2;
1689
1690   gMC->Gsvolu("TPSR","TUBE",idtmed[7],dm,0); // inner and outer rods differ
1691
1692
1693   for(Int_t nrod=0;nrod<18;nrod++){
1694     Float_t angle=innerOpenAngle*(Float_t)nrod;
1695
1696     xc=81.5*TMath::Cos(angle);
1697     yc=81.5*TMath::Sin(angle);
1698
1699     dm[2]=126.7;
1700
1701     gMC->Gsposp("TPSR",nrod+1,"TDGN",xc,yc,126.9,0,"ONLY",dm,3);
1702     gMC->Gsposp("TPSR",nrod+19,"TDGN",xc,yc,-126.9,0,"ONLY",dm,3);
1703
1704     dm[2]=126.6;
1705
1706     xc=254.25*TMath::Cos(angle);
1707     yc=254.25*TMath::Sin(angle);
1708
1709     // rod number 54 contans the HV cable
1710
1711     if(nrod<17) {
1712       gMC->Gsposp("TPSR",nrod+37,"TDGN",xc,yc,127.,0,"ONLY",dm,3);
1713       gMC->Gsposp("TPSR",nrod+54,"TDGN",xc,yc,-127.,0,"ONLY",dm,3);
1714     }
1715
1716   }
1717
1718   //----------------------------------------------------------
1719   // Tpc High Voltage Rod - MAKROLON + Copper cable
1720   //----------------------------------------------------------
1721
1722   // rod with cable (Left)
1723
1724   dm[0]=0.;
1725   dm[1]=2.25;
1726   dm[2]=126.6;
1727
1728   gMC->Gsvolu("THVL","TUBE",idtmed[7],dm,3);
1729
1730   // HV cable
1731
1732   dm[0]=0.;
1733   dm[1]=0.3;
1734   dm[2]=126.6;
1735
1736   gMC->Gsvolu("THVC","TUBE",idtmed[10],dm,3);
1737
1738   // empty space
1739
1740   dm[0]=0.3;
1741   dm[1]=1.;
1742   dm[2]=126.6;
1743
1744   gMC->Gsvolu("THVE","TUBE",idtmed[1],dm,3);
1745
1746   gMC->Gspos("THVC",1,"THVL",0.,0.,0.,0,"ONLY");
1747   gMC->Gspos("THVE",1,"THVL",0.,0.,0.,0,"ONLY");
1748
1749   // rod without cable
1750
1751   dm[0]=1.8;
1752   dm[1]=2.25;
1753   dm[2]=126.6;
1754
1755   gMC->Gsvolu("THVR","TUBE",idtmed[7],dm,3);
1756
1757   gMC->Gspos("THVL",1,"TDGN",xc,yc,-127.,0,"ONLY");
1758   gMC->Gspos("THVR",1,"TDGN",xc,yc,127.,0,"ONLY");
1759
1760   gMC->Gspos("TDGN",1,"TPC ",0.,0.,0.,0,"ONLY");
1761
1762   // services wheel cover -> wheel
1763
1764
1765   gMC->Gspos("TSWC",1,"TSSW",0.,0.,4.5,0,"ONLY");
1766   gMC->Gspos("TSWC",2,"TSSW",0.,0.,-4.5,0,"ONLY");
1767
1768
1769   // put the wheel into the TPC
1770
1771   gMC->Gspos("TSSW",1,"TPC ",0.,0.,278.7,0,"ONLY");
1772   gMC->Gspos("TSSW",2,"TPC ",0.,0.,-278.7,0,"ONLY");
1773
1774   //
1775
1776   gMC->Gsord("TPMW",6);
1777   gMC->Gsord("TSSW",6);
1778   gMC->Gsord("TSWC",6);
1779   if(fSecAL >=0)  gMC->Gsord("TPLS",3);
1780   if(fSecAU >=0 && fSens >0)  gMC->Gsord("TPUS",3);
1781   gMC->Gsord("TDGN",6);
1782
1783   // put the TPC into ALIC (main mother volume)
1784
1785   gMC->Gspos("TPC ",1,"ALIC",0.,0.,0.,0,"ONLY");
1786
1787
1788
1789 } // end of function
1790
1791 //_____________________________________________________________________________
1792 void AliTPCv2::DrawDetector()
1793 {
1794   //
1795   // Draw a shaded view of the Time Projection Chamber version 1
1796   //
1797
1798   // Set everything unseen
1799   gMC->Gsatt("*", "seen", -1);
1800   //
1801   // Set ALIC mother transparent
1802   gMC->Gsatt("ALIC","SEEN",0);
1803   //
1804   // Set the volumes visible
1805   //
1806
1807   gMC->Gsatt("TPC ","SEEN",0);
1808   gMC->Gsatt("TOIN","SEEN",1);
1809   gMC->Gsatt("TOIN","COLO",7);
1810   gMC->Gsatt("TOCV","SEEN",1);
1811   gMC->Gsatt("TOCV","COLO",4);
1812   gMC->Gsatt("TSA1","SEEN",0);
1813   gMC->Gsatt("TSA2","SEEN",0);
1814   gMC->Gsatt("TSA3","SEEN",0);
1815   gMC->Gsatt("TSA4","SEEN",0);
1816   gMC->Gsatt("TSA5","SEEN",0);
1817   gMC->Gsatt("TOFC","SEEN",1);
1818   gMC->Gsatt("TOFC","COLO",4);
1819   gMC->Gsatt("TSA6","SEEN",0);
1820   gMC->Gsatt("TSA7","SEEN",0);
1821   gMC->Gsatt("TSA8","SEEN",0);
1822   gMC->Gsatt("TIIN","SEEN",1);
1823   gMC->Gsatt("TIIN","COLO",7);
1824   gMC->Gsatt("TII1","SEEN",0);
1825   gMC->Gsatt("TIFC","SEEN",1);
1826   gMC->Gsatt("TIFC","COLO",4);
1827   gMC->Gsatt("TSA9","SEEN",0);
1828   gMC->Gsatt("TS10","SEEN",0);
1829   gMC->Gsatt("TS11","SEEN",0);
1830   gMC->Gsatt("TS12","SEEN",0);
1831   gMC->Gsatt("TS13","SEEN",0);
1832   gMC->Gsatt("TS14","SEEN",0);
1833   gMC->Gsatt("TICC","SEEN",0);
1834   gMC->Gsatt("TICM","SEEN",0);
1835   gMC->Gsatt("TS15","SEEN",0);
1836   gMC->Gsatt("TS16","SEEN",0);
1837   gMC->Gsatt("TS17","SEEN",0);
1838   gMC->Gsatt("TS18","SEEN",0);
1839   gMC->Gsatt("TS19","SEEN",0);
1840   gMC->Gsatt("TPJ1","SEEN",0);
1841   gMC->Gsatt("TPJ2","SEEN",0);
1842   gMC->Gsatt("TICS","SEEN",0);
1843   gMC->Gsatt("TDGN","SEEN",0);
1844   gMC->Gsatt("TIRC","SEEN",0);
1845   gMC->Gsatt("TIC1","SEEN",1);
1846   gMC->Gsatt("TIPP","SEEN",0);
1847   gMC->Gsatt("TIC3","SEEN",0);
1848   gMC->Gsatt("TRCE","SEEN",0);
1849   gMC->Gsatt("TPSC","SEEN",0);
1850   gMC->Gsatt("TPCC","SEEN",0);
1851   gMC->Gsatt("TORC","SEEN",0);
1852   gMC->Gsatt("TOPP","SEEN",0);
1853   gMC->Gsatt("TOC3","SEEN",0);
1854   gMC->Gsatt("TOC1","SEEN",1);
1855   gMC->Gsatt("TSSW","SEEN",1);
1856   gMC->Gsatt("TSWC","SEEN",1);
1857   gMC->Gsatt("TSSW","COLO",3);
1858   gMC->Gsatt("TSWC","COLO",3);
1859   gMC->Gsatt("TSCE","COLO",6);
1860   gMC->Gsatt("TSCE","SEEN",1);
1861   gMC->Gsatt("TWES","SEEN",0);
1862   gMC->Gsatt("TSWB","SEEN",0);
1863   gMC->Gsatt("TPEL","SEEN",0);
1864   gMC->Gsatt("TPMW","SEEN",1);
1865   gMC->Gsatt("TESR","SEEN",1);
1866   gMC->Gsatt("TPMW","COLO",12);
1867   gMC->Gsatt("TIC1","COLO",5);
1868   gMC->Gsatt("TOC1","COLO",5);
1869   gMC->Gsatt("TESB","SEEN",0);
1870   gMC->Gsatt("THVM","SEEN",1);
1871   gMC->Gsatt("THVM","COLO",11);
1872   gMC->Gsatt("THVH","SEEN",0);
1873   gMC->Gsatt("TPSR","SEEN",0);
1874   gMC->Gsatt("THVL","SEEN",0);
1875   gMC->Gsatt("THVC","SEEN",0);
1876   gMC->Gsatt("THVE","SEEN",0);
1877   gMC->Gsatt("THVR","SEEN",0);
1878   gMC->Gsatt("TPSS","SEEN",0);
1879   gMC->Gsatt("TPUS","SEEN",0);
1880   gMC->Gsatt("TPLS","SEEN",0);
1881
1882   //
1883   gMC->Gdopt("hide", "on");
1884   gMC->Gdopt("shad", "on");
1885   gMC->Gsatt("*", "fill", 7);
1886   gMC->SetClipBox(".");
1887   gMC->SetClipBox("TPMW",-300,300,-300,300,254.,270.);
1888   gMC->SetClipBox("TESR",-300,300,-300,300,254.,270.);
1889   gMC->SetClipBox("TSSW",-300,300,-300,300,283.,284.);
1890   gMC->SetClipBox("TSWC",-300,300,-300,300,283.,284.);
1891   gMC->SetClipBox("*", 0, 300, -300, 300, -290, 290);
1892   gMC->DefaultRange();
1893   gMC->Gdraw("alic", 40, 30, 0, 12, 9.5, .025, .025);
1894   gMC->Gdhead(1111, "Time Projection Chamber");
1895   gMC->Gdman(18, 4, "MAN");
1896   gMC->Gdopt("hide","off");
1897 }
1898
1899 //_____________________________________________________________________________
1900 void AliTPCv2::CreateMaterials()
1901 {
1902   //
1903   // Define materials for version 2 of the Time Projection Chamber
1904   //
1905
1906   AliTPC::CreateMaterials();
1907 }
1908
1909 //_____________________________________________________________________________
1910 void AliTPCv2::Init()
1911 {
1912   //
1913   // Initialises version 2 of the TPC after that it has been built
1914   //
1915
1916   Int_t *idtmed = fIdtmed->GetArray();
1917
1918   AliTPC::Init();
1919
1920
1921
1922   fIdSens=gMC->VolId("TPSS");
1923
1924   fIdLSec=gMC->VolId("TPLS"); // lower sector
1925   fIdUSec=gMC->VolId("TPUS"); // upper sector
1926
1927   gMC->SetMaxNStep(30000); // max. number of steps increased
1928
1929   gMC->Gstpar(idtmed[2],"LOSS",5); // specific energy loss
1930
1931   printf("%s: *** TPC version 2 initialized ***\n",ClassName());
1932   printf("%s: Maximum number of steps = %d\n",ClassName(),gMC->GetMaxNStep());
1933
1934   //
1935
1936 }
1937
1938 //_____________________________________________________________________________
1939 void AliTPCv2::StepManager()
1940 {
1941   //
1942   // Called for every step in the Time Projection Chamber
1943   //
1944
1945   //
1946   // parameters used for the energy loss calculations
1947   //
1948   const Float_t kprim = 14.35; // number of primary collisions per 1 cm
1949   const Float_t kpoti = 20.77e-9; // first ionization potential for Ne/CO2
1950   const Float_t kwIon = 35.97e-9; // energy for the ion-electron pair creation
1951
1952
1953   const Float_t kbig = 1.e10;
1954
1955   Int_t id,copy;
1956   Float_t hits[4];
1957   Int_t vol[2];
1958   TLorentzVector p;
1959
1960   vol[1]=0; // preset row number to 0
1961
1962   //
1963
1964   gMC->SetMaxStep(kbig);
1965
1966   if(!gMC->IsTrackAlive()) return; // particle has disappeared
1967
1968   Float_t charge = gMC->TrackCharge();
1969
1970   if(TMath::Abs(charge)<=0.) return; // take only charged particles
1971
1972   // check the sensitive volume
1973
1974   id = gMC->CurrentVolID(copy); // current volume Id
1975
1976   if (gMC->IsTrackEntering() && ( (id == fIdLSec) || (id == fIdUSec))){
1977     //    printf("track  %d entering volume %d\n",gAlice->CurrentTrack(),id);
1978     TLorentzVector p;
1979     TLorentzVector x;
1980     gMC->TrackMomentum(p);
1981     gMC->TrackPosition(x);
1982     AddTrackReference(gAlice->CurrentTrack(),p,x,gMC->TrackLength());
1983   }
1984
1985   if (gMC->IsTrackExiting() && ( (id == fIdLSec) || (id == fIdUSec))){
1986     //    printf("track  %d exiting volume %d\n",gAlice->CurrentTrack(),id);
1987     TLorentzVector p;
1988     TLorentzVector x;
1989     gMC->TrackMomentum(p);
1990     gMC->TrackPosition(x);
1991     AddTrackReference(gAlice->CurrentTrack(),p,x,gMC->TrackLength());
1992   }
1993
1994
1995   if(id == fIdLSec){
1996     vol[0] = copy-1; // lower sector number
1997   }
1998   else if(id == fIdUSec){
1999     vol[0] = copy+fTPCParam->GetNInnerSector()-1; // upper sector number
2000   }
2001   else if(id == fIdSens && gMC->IsTrackEntering()){
2002
2003     // track is entering the sensitive strip
2004
2005     vol[1]= copy-1; // row number (absolute)
2006
2007     // sector type
2008
2009     id = gMC->CurrentVolOffID(1,copy);
2010
2011     if(id == fIdLSec){
2012
2013       // lower sector
2014
2015       vol[0] = copy-1; // sector number
2016
2017     }
2018     else {
2019
2020       // upper sector
2021
2022       vol[0] = copy-1+fTPCParam->GetNInnerSector(); // sector number
2023       vol[1] -= fTPCParam->GetNRowLow(); // row number (starts also from 0)
2024
2025     }
2026
2027     if(vol[1] == 0){
2028
2029       // because Jouri wants to have this
2030
2031       gMC->TrackMomentum(p);
2032       hits[0]=p[0];
2033       hits[1]=p[1];
2034       hits[2]=p[2];
2035       hits[3]=0.; // this hit has no energy loss
2036       // new(lhits[fNhits++]) AliTPChit(fIshunt,gAlice->CurrentTrack(),vol,hits);
2037
2038       AddHit(gAlice->CurrentTrack(), vol,hits);  //MI change
2039
2040     }
2041
2042      gMC->TrackPosition(p);
2043      hits[0]=p[0];
2044      hits[1]=p[1];
2045      hits[2]=p[2];
2046      hits[3]=0.; // this hit has no energy loss
2047      // new(lhits[fNhits++]) AliTPChit(fIshunt,gAlice->CurrentTrack(),vol,hits);
2048
2049      AddHit(gAlice->CurrentTrack(), vol,hits);  //MI change
2050
2051   }
2052   else return;
2053
2054   //-----------------------------------------------------------------
2055   //  charged particle is in the sensitive volume
2056   //-----------------------------------------------------------------
2057
2058   if(gMC->TrackStep() > 0) {
2059
2060     Int_t nel = (Int_t)(((gMC->Edep())-kpoti)/kwIon) + 1;
2061     nel=TMath::Min(nel,300); // 300 electrons corresponds to 10 keV
2062
2063     gMC->TrackPosition(p);
2064     hits[0]=p[0];
2065     hits[1]=p[1];
2066     hits[2]=p[2];
2067     hits[3]=(Float_t)nel;
2068
2069     // Add this hit
2070
2071     // new(lhits[fNhits++]) AliTPChit(fIshunt,gAlice->CurrentTrack(),vol,hits);
2072     if (fHitType&&2){
2073       gMC->TrackMomentum(p);
2074       Float_t momentum = TMath::Sqrt(p[0]*p[0]+p[1]*p[1]);
2075       Float_t precision =   (momentum>0.1) ? 0.002 :0.01;
2076       fTrackHits->SetHitPrecision(precision);
2077     }
2078     AddHit(gAlice->CurrentTrack(), vol,hits);  //MI change
2079
2080   }
2081
2082   // Stemax calculation for the next step
2083
2084   Float_t pp;
2085   TLorentzVector mom;
2086   gMC->TrackMomentum(mom);
2087   Float_t ptot=mom.Rho();
2088   Float_t betaGamma = ptot/gMC->TrackMass();
2089
2090   Int_t pid=gMC->TrackPid();
2091   if((pid==kElectron || pid==kPositron) && ptot > 0.002)
2092     {
2093       pp = kprim*1.58; // electrons above 20 MeV/c are on the plateau!
2094     }
2095   else
2096     {
2097
2098       betaGamma = TMath::Max(betaGamma,(Float_t)7.e-3); // protection against too small bg
2099       pp=kprim*BetheBloch(betaGamma);
2100
2101       if(TMath::Abs(charge) > 1.) pp *= (charge*charge);
2102     }
2103
2104   Double_t rnd = gMC->GetRandom()->Rndm();
2105
2106   gMC->SetMaxStep(-TMath::Log(rnd)/pp);
2107
2108 }
2109
2110 //_____________________________________________________________________________
2111 Float_t AliTPCv2::BetheBloch(Float_t bg)
2112 {
2113   //
2114   // Bethe-Bloch energy loss formula
2115   //
2116   const Double_t kp1=0.76176e-1;
2117   const Double_t kp2=10.632;
2118   const Double_t kp3=0.13279e-4;
2119   const Double_t kp4=1.8631;
2120   const Double_t kp5=1.9479;
2121
2122   Double_t dbg = (Double_t) bg;
2123
2124   Double_t beta = dbg/TMath::Sqrt(1.+dbg*dbg);
2125
2126   Double_t aa = TMath::Power(beta,kp4);
2127   Double_t bb = TMath::Power(1./dbg,kp5);
2128
2129   bb=TMath::Log(kp3+bb);
2130
2131   return ((Float_t)((kp2-aa-bb)*kp1/aa));
2132 }
2133
2134